ABSTRACT Combustible cigarettes are the most deadly form of tobacco, but public misperceptions exist about the relative risk of lower harm products such as snus and e-cigarettes. As such, tobacco control professionals have advocated that smokers be better informed of these reduced risks given that this may facilitate switching to these reduced risk products from combustible cigarettes, and subsequent harm-reduction benefits (e.g., lower lung cancer risk). Tobacco companies are also beginning to apply to the FDA for permission to make reduced risk claims in their advertising, and this trend is likely to continue as the industry moves the market towards developing products with reduced risks relative to cigarettes. However, very little is known about how to communicate reduced risk (RR) tobacco messages, where they should be placed, how consumers might perceive them, and what their effects might be. Only a few studies have begun exploring the impact of RR messages presented as a benefit claim on smokeless tobacco or e-cigarette advertisements, or presented within a warning label that is required on ads. No studies have compared one approach versus the other, nor their potentially different impacts on important outcomes such as perceived message source, credibility, recall, risk perceptions, and use intentions. Similarly, little research exists on the impact of tobacco reduced risk information included in educational types of materials, such as fact sheets. In contrast to ads, health education materials may give consumers a fuller understanding of both the potential risks and risks relative to cigarettes, and could be used by health organizations or act as packaging inserts. As such, the overall goal of this study is to advance understanding of communication about reduced risk tobacco products. The specific aims are to: 1) develop tobacco reduced risk messages for short and long communication formats; 2) compare the impact of reduced risk messages presented as ad benefit claims versus within ad warning labels and 3) examine the impact of snus and e-cigarette educational fact sheets with reduced risk information. This project aims to address an important and timely research gap and produce high impact practical results that can immediately be used to guide industry regulations on tobacco risk communication and the development of tobacco educational materials that address relative tobacco product risks.